The invention relates to an encoding system comprising a subband coder for subband coding of a wideband digital signal, for example, a digital stereo audio signal, constituted by at least first and second signal components which are sampled each with a specific sampling frequency F.sub.3, the subband coder including signal splitting means for generating, in response to the wideband digital signal, a number of M subband signals by means of a sampling frequency reduction, for which purpose the splitting means split up the wideband signal into successive subbands having band numbers m which augment with frequency, where m=1.ltoreq.m.ltoreq.M, and in which each subband signal is constituted by at least first and second subband signal components, the encoding system further including quantizing means for quantizing block-by-block the first and second subband signal components in a subband SB.sub.m, a quantized subband signal component comprising successive signal blocks, each signal block containing q samples, the q samples in corresponding signal blocks of the first and second quantized subband signal components in the subband SB.sub.m being represented by n.sub.m1 and n.sub.m2 bits respectively, the quantizing means to this end comprising bit need determining means for determining a bit need b for corresponding signal blocks in the subbands, which bit need is related to the number of bits by which the samples in a signal block in a subband SB should be represented, and the quantizing means including bit allocation means for allocating the available quantity of bits to samples in the different signal blocks in the subbands in response to the bit needs as they are determined in the bit need determining means so as to obtain the values n.sub.m1 and n.sub.m2 for the corresponding signal blocks in the subband SB.sub.m.
Such an encoding system is known from European Patent Application No. 289.080 (to which U.S. Pat. No. 4,896,362 corresponds) document (1) in the reference list. Dutch Patent Application No. 90.01.127 (to which U.S. patent application Ser. No. 07/620,971 corresponds, abandoned; and U.S. patent application Ser. No. 08/144,092 which is an indirect continuation thereof, corresponds), document (6a) in the reference list, further describes how the bit allocation in such an encoding system may be realised. A single subband signal in each of the subbands, for example, a mono signal or two or more signals in each of the subbands may be concerned. With two signals one may think of a stereo signal, with three signals one may think of a left, central, right signal and with four signals one may think of a quadraphonic signal.